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Allergy: anaphylactic shock, nettle rash, Quincke’s edema. Toxicallergic affections of skin and mucosa. Etiology, pathogenesis. Diagnostics. Clinical picture. Complications. Principles of treatment. The role of a doctor-dentist in early diagnostics and prophylaxis.
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Allergy: anaphylactic shock, nettle rash, Quincke’s edema. Toxicallergic affections of skin and mucosa. Etiology, pathogenesis. Diagnostics. Clinical picture. Complications. Principles of treatment. The role of a doctor-dentist in early diagnostics and prophylaxis. Khabarova N.A.
Allergic reactions are sensitivities to substances called allergens that come into contact with the skin, nose, eyes, respiratory tract, and gastrointestinal tract. They can be breathed into the lungs, swallowed, or injected. Allergic reactions are common. The immune response that causes an allergic reaction is similar to the response that causes hay fever. Most reactions happen soon after contact with an allergen. • Many allergic reactions are mild, while others can be severe and life-threatening. They can be confined to a small area of the body, or they may affect the entire body. The most severe form is called anaphylaxis or anaphylactic shock.
Causes • Common allergens include: • Animal dander • Bee stings or stings from other insects • Foods, especially nuts, fish, and shellfish • Insect bites • Medications • Plants • Pollens
Trends in age and sex standardised admission rates for anaphylaxis, angio-oedema, food allergy, and urticaria, with rate ratios (RR) and 95% confidence intervals, England 1990-2001
Control of the immune system by the hypothalamo-pituitary axis during an antigen attack.
Formation of sensitised lymphocytes, lymphokines and antibodies. B-lymphocytes are involved in acquired, humoral immunity, and T-lymphocytes in congenital, cellular immunity.
Anaphylaxis is a severe, systemic allergicreaction • multisystem involvement, including the skin, airway, vascular system, and GI • Severe cases may result in complete obstruction of the airway, cardiovascular collapse, and death • Anaphylactoid or pseudoanaphylactic reactions display a similar clinical syndrome, but they are not immune-mediated. Treatment for the two conditions is similar
Etiology Pharmacologic agents • Antibiotics (especially parenteral penicillins and other ß-lactams), • aspirin and nonsteroidal anti-inflammatory drugs • intravenous (IV) contrast agents are the most frequent medications associated with life-threatening anaphylaxis. Latex Stinging insects ants, bees, hornets, wasps, and yellow jackets. Foods Peanuts, seafood, and wheat are the foods most frequently associated with life-threatening anaphylaxis.
Symptoms • Common symptoms of a mild allergic reaction include: • Hives (especially over the neck and face) • Itching • Nasal congestion • Rashes • Watery, red eyes
Anaphylactic reaction as it occurs in mast cells and basophils.
Symptoms • Symptoms develop quickly, often within seconds or minutes. They may include the following: • Abdominal pain • Abnormal (high-pitched) breathing sounds • Anxiety • Chest discomfort or tightness • Cough • Diarrhea • Difficulty breathing • Difficulty swallowing • Dizziness or light-headedness • Hives, itchiness • Nasal congestion • Nausea or vomiting • Palpitations • Skin redness • Slurred speech • Swelling of the face, eyes, or tongue • Unconsciousness • Wheezing
Signs and tests • Signs include: • Abnormal heart rhythm (arrhythmia) • Fluid in the lungs (pulmonary edema) • Hives • Low blood pressure • Mental confusion • Rapid pulse • Skin that is blue from lack of oxygen or pale from shock • Swelling (angioedema) in the throat that may be severe enough to block the airway • Swelling of the eyes or face • Weakness • Wheezing • The health care provider will wait to test for the allergen that caused anaphylaxis (if the cause is not obvious) until after treatment.
Treatment • Anaphylaxis is an emergency condition that needs professional medical attention right away. If necessary, begin rescue breathing and CPR. • If the allergic reaction is from a bee sting, scrape the stinger off the skin. • Take steps to prevent shock. Have the person lie flat, raise the person's feet. • endotracheal intubation or tracheostomy or cricothyrotomy. • The person may receive antihistamines, such as diphenhydramine, and corticosteroids, such as prednisone, to further reduce symptoms (after lifesaving measures and epinephrine are given).
Allergic Angioedema/Urticaria • Reactions are induced by histamine and mediated by IgE • IgE mediated hypersensitivity reaction • Reaction with allergen induces the release of histamine and other mediators • Result: vasodilatation and edema
Allergic Angioedema/Urticaria Biochemistry: • Dependent on presence IgE molec sp to proteins in causative agent • IgE molec bind to patients mast cells • Trigger rxn upon re-exposure to antigen
Allergic Angioedema/Urticaria Inciting Agents: • Medications • Foods • Latex • Environmental (includes insect bites)
Allergic Angioedema/Urticaria Clinical Presentation: • Highly variable • Depends on: • prev sensitization • type of allergen • +/- urticaria (pruritic)
Allergic Angioedema/Urticaria Clinical Presentation: • Often seen in patients with other allergic conditions: • Atopic dermatitis • Allergic rhinitis • Asthma
Urticaria Urticaria
Physical urticaria Solar urticaria Cold urticaria
Physical urticaria Aquagenic urticaria Heat urticaria
Cholinergic Physical urticaria Dermatographic
Algorithm for diagnosis of angio-oedema due to C1-inhibitor deficiency.